Merge /home/v4l/v4l/patchwork

* /home/v4l/v4l/patchwork: (50 commits)
  [media] v4l2-ctrls.c: add support for V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK
  [media] v4l2-event.h: add overview documentation to the header
  [media] v4l2-ctrls/v4l2-events: small coding style cleanups
  [media] DocBook: update V4L Event Interface section
  [media] v4l2-framework.txt: update v4l2_event section
  [media] v4l2-framework.txt: updated v4l2_fh_init documentation
  [media] v4l2-ctrls: v4l2_ctrl_handler_setup code simplification
  [media] v4l2-ctrls: split try_or_set_ext_ctrls()
  [media] v4l2-ctrls: improve discovery of controls of the same cluster
  [media] v4l2-ctrls: don't initially set CH_VALUE for write-only controls
  [media] v4l2-event: add optional merge and replace callbacks
  [media] v4l2-event/ctrls/fh: allocate events per fh and per type instead of just per-fh
  [media] v4l2-ctrls/event: remove struct v4l2_ctrl_fh, instead use v4l2_subscribed_event
  [media] v4l2-events/fh: merge v4l2_events into v4l2_fh
  [media] V4L: ov9740: Add suspend/resume
  [media] V4L: ov9740: Reorder video and core ops
  [media] V4L: ov9740: Remove hardcoded resolution regs
  [media] V4L: ov9740: Fixed some settings
  [media] V4L: ov9740: Correct print in ov9740_reg_rmw()
  [media] V4L: ov9740: Cleanup hex casing inconsistencies
  ...